Magician in Camelot (6)
I believe the answer is:
'magician in camelot' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for merlin that I've seen before include "Arthur's sorcerer" , "one that cast a spell in Arthur's court" , "Flighty type" , "Legendary magician" , "Magician of legend - falcon" .)